H Shintani and F Hayashi
A high-performance liquid chromatography (HPLC) method using an internal standard is validated for the determination of 4-amino-6-methoxy-1-phenyl-pyridozinium methyl sulfate (ameziniummetilsulfate, AM) in a uremia patient treated by artificial dialysis. The method involves liquid-liquid extraction and ion-suppressed reverse-phase HPLC on an end-capped C-18 column. There is no interference by plasma components or AM metabolites in the HPLC analysis. Average recovery rate using liquid -liquid extraction was 88.7% and limit of determination (LOD) was 2 ng/ml. This concentration was sufficient to determine AM in human plasma. Accuracy and precision was < 5.6% and 16.2%, respectively, at 2 ng/ml, LOD.